Need some help from some of you wise Mopar masters.

I just purchased a new / used Dana 60 rear end from a swap meet. The rear end came out of a narrowed 69 roadrunner (Not a factory rear end... It looks likea mid 80's rear end). What I want to do is install the Dana 60 under my 1969 dodge charger without narrowing my car. Now the problem….I need new axels and tubes so I called Strange to order new axels and tubes for the rear end and was told to send them the exact size and length of tubes and axels. I know this is an easy thing for you Mopar masters but for me it’s not. Can someone help me out with this… I have asked a few people around my parts and received 3 different measurements. It seems that everyone has the correct way of measuring and the other guy’s measurements are wrong. What I can tell you is that all I want is the rear end to be the correct size in length.

What I have now.

The Dana 60 I bought has marks on both sides of the axel housing assembly. On the right the numbers are 248 and under the number is a second number 48543 …… On the left side I found the letter A and under that is the number 8012. My Charger has the factory rear end under it now but has no axels … just the bear empty housing.

Any help with be appreciated. Thank you